Automatic timer for photo-timing machines



June 28, 1932. c. DOlNO 1,865,397

AUTOMATIC TIMER FOR PHOTO TIMING MACHINES Filed March 1'7, 1930 2 Sheets-Sheet l June 28, 1932. c. DOINO' AUTOMATICTIMER FOR PHOTO TIMING MACHINES Filed March 17, 1930 2 Sheets-Sheet 2 Patented June 28, 1932 PATENT OFFICE CABMINE DOINO, OF NEW HAVEN, CONNECTICUT AUTOMATIC TIMER FOR PHOTO-TIMING MACHINES Application filed March 17, 1930. Serial No. 436,612.

This invention relates to an automatic tlmer for use in connection with a photoprinting machine, and more particularly for timing exposures for developing papers, pho- 5 tographs and the like.

The primary object of this invention is to provide a device which is so arranged as to close the printing light circuit periodically, and which can be adjusted for various time lengths of exposure. This eliminates the present time printing ractice which is car ried on by the use 0 a time clock which necessarily must be Watched by the person printing and who puts on the printing light at a given time and shuts it off after the length of exposure required is reached.

Another object of this invention is to produce a device which is so simple in operation that a mere child would be capable of operating it. As this mechanism is entirely automatic, it eliminates the assistance of a skilled photographer and assures to any operator thereof a uniform shade in the various printings.

It is a further object of this invention to produce a machine which can be constructed so cheaply that even the small photographers will be able to buy one.

With these and other objects in view, the

39 invention resides in a certain novel construction and combination and arrangement of parts, the essential features of which arehereinafter fully described and are illustrated in the accompanying drawings in which,

Figure I is a view in front elevation of the automatic timing device showing the parts in their respective positions when the device is at rest;

Figure II is a side view thereof with the casing in section.

Figure III is a view corresponding to Figure I, showing the parts in position when the device is set for a time interval of approximately fifteen seconds.

Figure IV is a detached perspective view of the circuit closing unit.

This mechanism is adapted for use in connection with a cabinet having one or more openings to receive photographic printing 63 frames, and within the cabinet, preferably a series of electric lights are arranged to illuminate the face of the printing frame when in circuit. v

In order to secure with accuracy the exact quantity of light necessary to print the pho- 5 tographs, I employ a motor 10, carrying at the outer end of its shaft a pinion, 11, meshing with a time train of gears 12. A gear wheel 13, fastened to a shaft 14, is driven by the time train at the speed of one revolu- 00 tion per minute. The shaft 14, passes "thru a dial plate 15, and at its forwardend carries a toothed wheel, but as herein shown a ratchet wheel 16, to which is integrally fastened a cup shaped drum or flange 17, of fibre or as other insulating material, which carries a plurality of spaced metal bands 18. Upon the said bands, brushes, or as herein shown,

a U shaped metallic finger, 31, mounted on a flash of insulating material 32, have contact 7 to impart current from any source of supply.

Loosely mounted on the shaft 14 and abut= ting against the dial plate 15, is an arm 19, carrying at the outer extremity an indexing pin'20, adapted to fit into recesses 21, in the 15' dial plate 15. Each of the recesses 21, is spaced sufficiently apart so as to make in the complete circle in all or one for each second in a minute.

The shaft 14, also carries loosely mounted so thereon an arm 22, which abuts against the arm 19. The arm 22, is provided with acircuit closing unit, comprising a pawl 23, pivoted on astud 24, which is adapted tofit the teeth 25, of the ratchet wheel 16. A 815 spring 26, exerts a constant effort to engage the pawl 23 with-the teeth of-the ratchet wheel 16. The pawl 23 carries a flexible switch arm 27, which is mounted on a flash of insulating material 28. The said pawl also carries a 00 pin '29, which is adapted to ride upon a cam finger 30, at the finish of the set time interval so as to break the circuit.

The operation of the machine is as follows: Arm 19, is manually pulled around and set If in the hole representing the number of seconds that light is desired for printing, fifteen for example. Current from any desirable source is then applied to the device which starts the motor causing the fibre gear to rotate. The arm 22, is then pulled around so as to directly overlie the arm 19, and the stud 24, is then sprung in place onto the gear tooth 25. The circuit to the printing machine is closed during the travel of the arm 22, from the set point to the zero point at which place the finger removes the stud 24:, from the gear and breaks the circuit. See Figure I. While the circuit is broken the printing machine, is prepared again and the arm 22, is again pulled around to overlie the arm 19, and the operation as outlined above is repeated.

The mechanism herein illustrated and described is capable of considerable modification without departing from the principle of this invention and may be used Wherever definite and accurate timing is the essential function and is not limited to a photographic printing machine.

Claims:

1. An automatic timer, comprising a constantly rotating gear, a timed motor rotating the same, a dial, a plurality of arms ad jacently pivoted thereto, a stud at the extremity of one of said arms for meshing with the teeth of said gear and means for removing said stud from the gear teeth, said other arm when properly positioned, being capable of controlling the time during which the other arm and gear teeth mesh.

2. An automatic timer, comprising a fiber gear, a dial, a plurality of arms adjacently pivoted thereto, a stud at the extremity of one of said arms and a metallic contact member secured adjacent to said stud, said gear having conduct-ing material thereon, over which the contact member slides.

3. An automatic timer, comprising a constantly rotating fibre gear, a laterally extending flange, integral with said gear, spaced metal bands on said flange, a dial, and a mechanism pivoted adjacent to said dial comprising an arm capable of meshing with the teeth of said gear, means, at the extremity of said arm for contacting with said metal bands to close a circuit, and a means for removing the arm from the teeth of said gear after the arm has moved through a definite interval.

4. An automatic timer, comprising a constantly rotating fibre gear, a laterally extending flange integral with said gear, a timed motor rotating said gear, spaced metal bands on said flange, a dial, and a mechanism pivoted adjacent to said dial comprising an arm capable of meshing with the teeth of said gear, means at the extremity of said arm for contacting with the metal bands to close a circuit, and a means for removing the arm from the teeth of the gear after the arm has moved through a definite time.

In testimony whereof, I have signed this specification.

CAR-MIN E DOINO. 

